Stimuli

All jokes were written in Mandarin Chinese and designed to elicit humor-related cognitive and affective processing, followed by the laughter response. Each joke structure consisted of two components: the setup and the punch line. Verbal jokes were selected from the database of Chinese jokes (Cheng et al., 2013; Chan, 2014) or from websites. The 80 jokes in Mandarin Chinese included 30 BJs, 20 EJs, and 30 AJs. The corresponding baseline conditions were constructed by replacing the punch lines with neutral (unfunny) stories of matching length and punctuation, including 30 bridging-inference baseline stimuli (BS), 20 exaggeration baseline stimuli (ES), and 30 ambiguity baseline stimuli (AS). The criteria for selecting the stimuli were described in greater detail in Chan and Lavallee (2015). Few EJs were used because the current study did not include nonsense jokes and jokes related to psychiatric hospitals and patients.

The BJs were constructed using the inferring consequences logical mechanism. For example, in the funny condition, one joke reads:

Jack dreamed of being a writer since he was little. His dream comes true at the age of thirty when his book is finally published. One month later, Jack asks his friend, “Have you read my book yet?” his friend says: “Yes, and I bought one.” Jack happily responds: “Oh, that was you! Thanks!”

The unfunny condition (BS) reads “Jack happily responds: ‘Thanks for buying it.”

The EJs were constructed using the exaggeration logical mechanism. For example:

A restaurant was renowned for its stinginess. One day, a customer ordered a plate of soup. The waiter placed a plate on the table and kept the man waiting for a long while. The man signaled the manager to come and said “You have kept me waiting and you want me to have this wet plate?” The manager smiled and said: “Sir, this is your soup.”

In the unfunny condition (ES), the Boss smiled and said: “Sir, I will get a new one for you.”

Finally, the AJs were constructed using the juxtaposition logical mechanism. For example, one joke read:

In kindergarten, the kids were ready for a nap after going to the toilet. Jane suddenly rushed into the classroom and told the teacher: “Teacher, there are ants in the toilet.” The teacher realized that the kids had just recently learned the English word “ant,” so the teacher wanted to know how well Jane learned the word. The teacher asked: “So, how about the ant?” Jane: “The ants didn’t say anything.”

In the unfunny condition (AS), Jane says: “I have no idea.” (The ambiguity is more clear in the Chinese original: the Chinese phrase “mayi ruhe shuo” can mean both “how do you say ant?” and “what did the ants have to say?”)

To ensure that the jokes were valid stimuli, behavioral pilot studies were conducted prior to the fMRI experiment. The participants rated each trial on a 9-point scale. The mean and standard deviation for comprehensibility was 8.25 ± 0.83, indicating that all stimuli (joke and non-joke) were comprehensible to the participants. The mean funniness rating for all joke types was 6.06 ± 1.65. A one-way repeated-measures ANOVA performed on the participants’ funniness ratings was significant, F(5,235) = 226.67, p < 0.001, η_p² = 0.83, and Bonferroni post hoc tests revealed that the funny conditions were significantly funnier than the unfunny conditions.